The present invention relates to a magazine, in particular a revolving magazine, for temporarily storing a plurality of joining elements, comprising a housing that can be fastened to a joining head, a rotary body that can be rotated about an annular axis, preferably in steps, by means of a drive motor, a plurality of chambers for receiving joining elements being formed on the rotary body, a loading arrangement by means of which joining elements can be loaded into the chambers, and an unloading arrangement by means of which the joining elements received in the chambers can be unloaded into a joining head.
The invention also relates to a joining apparatus having a joining head that comprises a holding device for holding a joining element and a magazine for temporarily storing a plurality of joining elements that can be transferred individually into the holding device by means of a transfer device.
Furthermore, the invention relates to a loading station for a joining apparatus.
The invention further relates to a supply arrangement for supplying joining elements, in particular for a loading station of the aforementioned type, comprising a supply tube, the first end of which can be connected to a joining element provision device and the second end of which can be connected to a loading station for loading a magazine of a joining head, the supply tube being arranged in an arc-like manner having a portion rising from the first end up to an apex point and a portion falling from the apex point to the second end, it being possible to supply a joining element from the first end towards the second end by means of compressed air.
Lastly, the invention relates to a method for loading an above-described magazine arranged on a joining head of an above-described joining apparatus.
In the field of joining technology, it is known to join joining elements, such as earthing bolts, to workpieces such as vehicle bodyworks. The joining process can involve welding the joining element to the workpiece, referred to as stud welding. It is also known to bond joining elements to workpieces in what is known as stud bonding. Moreover, it is known to use joining elements to produce joints. Joining elements of this kind can be rivets for example, in particular punch rivets, used to connect/rivet two or more workpieces together.
In vehicle bodywork construction, joining processes of this kind are widely used. Punch rivets are used, for example, to connect bodywork sheets. Joining elements such as plastics bolts or metal bolts are joined, i.e. welded or bonded to bodywork portions, these joining elements then being able to be used as anchors for additional fastening tasks or as earthing bolts for earthing the vehicle electronics. In this case, it is known to attach plastics or metal clips to bolts that protrude from a sheet, which clips are then used to secure wires or cable strands to the bodywork. It is also known to fasten vehicle interior parts to protruding bolts.
To carry out such joining processes, joining apparatuses that are often mounted on robots are used, particularly in bodywork construction. It is particularly advantageous in this case if a high clock rate can be achieved in the joining processes. Therefore, the joining elements used are preferably supplied to the joining apparatus in an automated manner. Typically, this occurs, for example, by a stationary supply device separating the joining elements and then conveying them to a joining head of the joining apparatus by means of compressed air via a supply tube. In the joining head, the joining element is then usually loaded into a holding device and held ready for the joining process.
However, using a flexible supply tube of this kind on a robotic joining head is disadvantageous in some respects. In particular, supply tubes of this kind are prone to increased wear, in particular due to the joining movement of the joining head and the associated high stresses on the supply tubes.
Supplying the elements by means of a supply tube leads to high blast air requirements. In addition, using flexible tubes can cause the tube to kink, which may lead to a joining robot stopping. This can result in the joining process sequence being held up. Moreover, supplying the elements via a supply tube entails long supply times.
To prevent this problem, it is known to secure a magazine to a robotic joining head. This magazine is preferably designed to receive a plurality of joining elements, meaning that an accordingly high number of joining processes can be carried out one after the other. Once the magazine is empty, the robot can move the joining head to a loading station at which the magazine is preferably refilled.
In magazines of this kind, the joining elements received therein are generally received directly adjacent to one another either axially or in the circumferential direction. It is known in this respect to clamp the joining elements in a chamber of a magazine of this kind. It is also known to convey joining elements into a larger chamber, in which case it must actively be ensured, for example by subsequently closing the chamber, that the joining elements remain in the chamber until they are eventually conveyed out of the magazine to the joining head.
For example, DE 10 2005 015 032 A1 discloses an apparatus for supplying joining elements to a preparation device, comprising a magazine for receiving the joining elements and a device that is connected to the magazine and intended for separating and transferring the joining elements to the preparation device, the magazine comprising a plurality of chambers, each chamber being intended for receiving just one joining element, the chambers forming a practically endless row, and a chamber being connectable to a supply channel at a first point and to a transfer channel at a second point, it being possible to actively block the channels to prevent the joining elements accidentally falling out.